a term used to describe the state of a fission reaction when the number of neutrons released by fission is exactly balanced by the neutrons being absorbed and escaping. For example, reactor is said to be "critical" when it achieves a self-sustaining nuclear chain reaction, as it does when the reactor is operating. [ Click "BackButton" for previous location
Mean number of the system failures during a mission phase because of a block or its failure mode. The criticality value is used to rank failure modes when performing a FMECA. Criticality for a severity, counts only the system failures of this severity because of a block or its failure mode .
A subjective description of the intended use and application of the system. Software criticality properties may include safety, security, complexity, reliability, performance, or other characteristics. [IEEE Stds Glossary